[settings] Add settings component

This adds a new settings component for user configurable options that
can be changed through the JSON API.
The settings are stored in the admin db table and not in the conf-file.

src/Makefile.am

@@ -122,6 +122,7 @@ forked_daapd_SOURCES = main.c \
 	smartpl_query.c smartpl_query.h \
 	player.c player.h \
 	worker.c worker.h \
+	settings.c settings.h \
 	input.h input.c \
 	inputs/file_http.c inputs/pipe.c \
 	outputs.h outputs.c \

src/settings.c

@@ -0,0 +1,153 @@
+/*
+ * Copyright (C) 2019 Christian Meffert <christian.meffert@googlemail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "settings.h"
+
+#include <stdbool.h>
+#include <string.h>
+
+#include "db.h"
+
+
+
+static struct settings_option webinterface_options[] =
+  {
+      { "show_composer_now_playing", SETTINGS_TYPE_BOOL },
+      { "show_composer_for_genre", SETTINGS_TYPE_STR },
+  };
+
+static struct settings_category categories[] =
+  {
+      { "webinterface", webinterface_options, ARRAY_SIZE(webinterface_options) },
+  };
+
+
+int
+settings_categories_count()
+{
+  return ARRAY_SIZE(categories);
+}
+
+struct settings_category *
+settings_category_get_byindex(int index)
+{
+  if (index < 0 || settings_categories_count() <= index)
+    return NULL;
+  return &categories[index];
+}
+
+struct settings_category *
+settings_category_get(const char *name)
+{
+  int i;
+
+  for (i = 0; i < settings_categories_count(); i++)
+    {
+      if (strcasecmp(name, categories[i].name) == 0)
+	return &categories[i];
+    }
+
+  return NULL;
+}
+
+int
+settings_option_count(struct settings_category *category)
+{
+  return category->count_options;
+}
+
+struct settings_option *
+settings_option_get_byindex(struct settings_category *category, int index)
+{
+  if (index < 0 || !category || category->count_options <= index)
+    return NULL;
+
+  return &category->options[index];
+}
+
+struct settings_option *
+settings_option_get(struct settings_category *category, const char *name)
+{
+  int i;
+
+  if (!category || !name)
+    return NULL;
+
+  for (i = 0; i < category->count_options; i++)
+    {
+      if (strcasecmp(name, category->options[i].name) == 0)
+	return &category->options[i];
+    }
+
+  return NULL;
+}
+
+int
+settings_option_getint(struct settings_option *option)
+{
+  if (!option || option->type != SETTINGS_TYPE_INT)
+    return 0;
+
+  return db_admin_getint(option->name);
+}
+
+
+bool
+settings_option_getbool(struct settings_option *option)
+{
+  if (!option || option->type != SETTINGS_TYPE_BOOL)
+    return false;
+
+  return db_admin_getint(option->name) > 0;
+}
+
+char *
+settings_option_getstr(struct settings_option *option)
+{
+  if (!option || option->type != SETTINGS_TYPE_STR)
+    return NULL;
+
+  return db_admin_get(option->name);
+}
+
+int
+settings_option_setint(struct settings_option *option, int value)
+{
+  if (!option || option->type != SETTINGS_TYPE_INT)
+    return -1;
+
+  return db_admin_setint(option->name, value);
+}
+
+int
+settings_option_setbool(struct settings_option *option, bool value)
+{
+  if (!option || option->type != SETTINGS_TYPE_BOOL)
+    return -1;
+
+  return db_admin_setint(option->name, value);
+}
+
+int
+settings_option_setstr(struct settings_option *option, const char *value)
+{
+  if (!option || option->type != SETTINGS_TYPE_STR)
+    return -1;
+
+  return db_admin_set(option->name, value);
+}

src/settings.h

@@ -0,0 +1,65 @@
+
+#ifndef __SETTINGS_H__
+#define __SETTINGS_H__
+
+#include <stdbool.h>
+
+
+enum settings_type {
+  SETTINGS_TYPE_INT,
+  SETTINGS_TYPE_BOOL,
+  SETTINGS_TYPE_STR,
+  SETTINGS_TYPE_CATEGORY,
+};
+
+struct settings_option {
+  const char *name;
+  enum settings_type type;
+};
+
+struct settings_category {
+  const char *name;
+  struct settings_option *options;
+  int count_options;
+};
+
+
+int
+settings_categories_count();
+
+struct settings_category *
+settings_category_get_byindex(int index);
+
+struct settings_category *
+settings_category_get(const char *name);
+
+int
+settings_option_count(struct settings_category *category);
+
+struct settings_option *
+settings_option_get_byindex(struct settings_category *category, int index);
+
+struct settings_option *
+settings_option_get(struct settings_category *category, const char *name);
+
+int
+settings_option_getint(struct settings_option *option);
+
+
+bool
+settings_option_getbool(struct settings_option *option);
+
+char *
+settings_option_getstr(struct settings_option *option);
+
+int
+settings_option_setint(struct settings_option *option, int value);
+
+int
+settings_option_setbool(struct settings_option *option, bool value);
+
+int
+settings_option_setstr(struct settings_option *option, const char *value);
+
+
+#endif /* __SETTINGS_H__ */